array(3) { [0]=> int(4399) [1]=> string(210) "Blaunstein N., and Christodoulou Ch. G. Radio Propagation and Adaptive Antennas for Wireless Communication Links - Terrestrial, Atmospheric and Ionospheric. Hoboken, New Jersey, Wiley Interscience, 2007. 614 p." [2]=> int(1) }